Device for a patient-specific acetabulum reaming and cup positioning guide

ABSTRACT

A device for use in total hip arthroplasty surgery including a first guide member having a substantially semi-circular ring having a top surface and a bottom surface, a plurality of first guide legs protruding vertically downward from the lower surface of the semi-circular ring, the first guide legs including a contact area disposed on the open end of the first guide leg; a plurality of holes disposed on the ring, a plurality of protrusions extending vertically upward from a top surface of the ring. The device also includes a second guide member having an arc having an arc of curvature substantially similar to the semi-circular ring, the arc having a top surface and bottom surface, first and second horizontal brackets connecting ends of the arc and being connected thereto at a termination point, a plurality of second guide legs protruding vertically from either the lower surface of the arc, first or second horizontal brackets; and means for connecting the second guide member to the first guide member. The device also includes third and fourth guide members.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This application is not the subject of any federally sponsored researchor development.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationNo. 61/841,964, which was filed in the U.S. Patent and Trademark Officeon Jul. 2, 2013, all of which is incorporated herein by reference in itsentirely for all purposes.

THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT

There has been no joint research agreements entered into with any thirdparties.

BACKGROUND OF THE INVENTION

Field of the Invention

The embodiments of the present invention relate generally to a devicefor a patient-specific acetabular reaming and cup positioning guide. Inparticular, the embodiments of the present invention are directed to adevice that includes a patient-specific guide and template for use intotal hip arthroplasty surgeries.

Background

Total Hip Arthroplasty (“THA”) is a complex orthopedic operation inwhich surgeons replace a diseased hip joint with implants. THA iscommonly performed to relieve joint pain and improve quality of life.Approximately 200,000 THA surgeries are performed each year in theUnited States, and the number is likely to reach 570,000 by the year2030. The current costs of THA surgery is approximately $25,000.

A rising percentage of patient research information about THA surgicaltechnologies and surgeons before making the final decision regardingsurgery. As a result, the THA market is driven by well-educated patientsand their demand for technological advances, which further drives theneed for improved acetabular reaming and positioning guides, and devicesdirected to the same.

As shown in FIGS. 11-13, which are explained in further detail below,the acetabulum is the socket of the hip bone, into which the head of thefemur fits. It is essentially a concave cavity that receives the femoralhead, where the femoral head is able to move (i.e., the ball shaped headon the top of the femur is able to rotate around in the concave cavityforming a “ball and socket” joint). Reaming is a process in whichsurgeons use a reamer to remove diseased bone and cartilage. Reamingalso determines the correct size and position of the socket inpreparation for the placement of acetabular component.

Properly reaming the acetabular socket and placing the implant in asuitable position and orientation is critical for the success of a THAsurgery. Inaccurate implant placement can contribute to variouscomplications such as bearing surface wear, implant dislocation, limblength discrepancy, component impingement, osteolysis, implantloosening, and premature or early failure. These complications can leadto hospital readmission and revision surgery, and can result in a poorclinical outcome and significantly increase healthcare costs.

Acetabular socket reaming and implant placement is a complicated andtime consuming procedure. In currently available surgical techniques,the dominant method is the traditional freehand method that involvesmaking a 4 to 8 inch incision on the side of the hip. The clinicaloutcome relies heavily on the surgeon's experience and onsite execution.Because the socket is deep within the incision and surrounded bymuscles, fat, and other soft tissues, it is difficult for evenwell-experienced and high-volume surgeons to consistently attain correctacetabular component orientation and position, especially for high bodymass index (“BMI”) patients. Minimally invasive surgery (“MIS”) allowsthe surgeon to perform the THA surgery through a smaller incision(approximately 3 to 6 inch). MIS incision candidates are typicallythinner, younger, healthier, and more motivated to have a quick recoveryand shorter hospital stay. However, MIS has not shown any betterlong-term clinical outcomes than traditional THA surgery. Its learningcurve is long and it is easier for new surgeons to make mistakes due tolimited vision of the surgical site.

Image-guided navigation surgery uses computer surgical planning todetermine the implant size and alignment preoperatively. The surgery isexecuted with the help of intraoperative implant registrationinstruments. The surgery can achieve high accuracy and consistency, butthe application has been jeopardized by high instrument costs, longoperative time, and a steep learning curve.

Use of patient-specific surgical guides/templates is a relatively newtechnique and has been used in the installation of dental implants. Itis usually designed in a computer surgical planning procedure based on apatient's bone geometry (three-dimensional reconstruction of CT or MRIimages) and then manufactured using medical grade plastic materials. Thetemplate can be fixed onto a unique area of the bone and includes astructure that can guide surgical tools through certain locations anddirections to remove bone with precision and place implants with properorientation consistently. The computer surgical plan is usually approvedby a surgeon and if properly designed and executed, the guide will helpthe surgeon replicate the plan in patients to achieve optimal implantposition and orientation. In recent years, surgical guides are becomingmore common in orthopedic surgeries. An example of a custom-fit surgicalguide for total knee arthroplasty (“TKA”) can be found in U.S. PatentApplication Publication No. 2010/0049195 to Park et al., entitled“Arthroplasty System and Related Methods.” Due to successful clinicaloutcomes, similar surgical guides have been used by more and moresurgeons to replace the costly navigation guided TKA surgery and reduceoperative time.

In the case of acetabular reaming and positioning guides currenttechniques have various limitations. For example in the guide describedin U.S. Patent Application Publication No. US 2012/0041445, the cylindermay be too big and can impinge with the femur even when the femoralhead/neck is removed, resulting in the guide not sitting in the intendedposition to achieve accurate reaming. Another issue is that the threelegs are too long. The surgeon will need to remove significant amountsof the soft tissue around the acetabular rim to allow the legs to sit atthe right locations. If this soft tissue is not removed, inaccuratelocation of the three legs will change the orientation and location ofthe reamer and eventually influence the accuracy of the implantplacement. The same issue exists in the guide disclosed in InternationalPatent Application Publication No. WO 2012/010366, wherein the threelegs require large soft tissue cuts and may lead to inaccurate reamerorientation and positioning. In addition, the reamer and its connectedguide part are not designed for easy installation, which is requiredduring the surgery to change reamers and remove bone.

There is currently a need for an improved THA surgical guide in themedical device market. Specifically, there exists a need for apatient-specific guide/template for both surgeons and patients of THA.The embodiments of the present invention properly solve the problems ofthe prior art.

SUMMARY OF THE INVENTION

For the reasons included above, it is therefore an object of embodimentsof the present invention to provide a device, system, and method thatincludes a patient-specific guide and template for use in THA surgeries.

The embodiments of the present invention include a device for use intotal hip arthroplasty surgery that includes first, second, third, andfourth guide members. The first guide member includes a substantiallysemi-circular ring having a top surface and a bottom surface, aplurality of first guide legs protruding vertically downward from thelower surface of the semi-circular ring, the first guide legs includinga contact area disposed on the open end of the first guide leg; aplurality of holes disposed on the ring, and a plurality of protrusionsextending vertically upward from a top surface of the ring. The secondguide member includes an arc having an arc of curvature substantiallysimilar to the semi-circular ring, the arc having a top surface andbottom surface, first and second horizontal brackets connecting ends ofthe arc and being connected thereto at a termination point, a pluralityof second guide legs protruding vertically from either the lower surfaceof the arc, first or second horizontal brackets; and means forconnecting the second guide member to the first guide member. The thirdguide member includes a cylindrical first tube; and a horizontal plateconnected to the tube having a top surface and a lower surface, wherethe lower surface includes the engagement surface for engagement withthe first guide member; and a plurality of holes disposed on the plate,where posts protruding from the top surface of the semi-circular ringare capable of entering the plurality of holes disposed on the plate toengage the first guide member with the third guide member. A fourthguide member includes a cylindrical second tube capable of beingconnected to the first tube, where the outside diameter of the secondtube is less than the inside diameter of the first tube to allowengagement; and means for engaging the second tube to the first tube.

Yet another embodiment of the present invention is directed to a devicefor use in total hip arthroplasty surgery including a first guide memberhaving a substantially semi-circular ring having a top surface and abottom surface, a plurality of first guide legs protruding verticallydownward from the lower surface of the semi-circular ring, the firstguide legs including a contact area disposed on the open end of thefirst guide leg; a plurality of holes disposed on the ring, a pluralityof protrusions extending vertically upward from a top surface of thering. The device also includes a third guide member having a cylindricalfirst tube; and a horizontal plate connected to the cylindrical firsttube having a top surface and a lower surface, where the lower surfaceincludes the engagement surface for engagement with the first guidemember; and a plurality of holes disposed on the plate, wherein postsprotruding from the top surface of the semi-circular ring are capable ofentering the plurality of holes disposed on the plate to engage thefirst guide member with the third guide member. The device also includesa fourth guide member including a cylindrical second tube capable ofbeing connected to the first tube, wherein the outside diameter of thesecond tube is less than the inside diameter of the first tube to allowengagement; and means for engaging the second tube to the first tube.

The embodiments of the present invention are further directed to adevice for use in total hip arthroplasty surgery that includes a firstguide member having a substantially semi-circular ring having a topsurface and a bottom surface, a plurality of first guide legs protrudingvertically downward from the lower surface of the semi-circular ring,the first guide legs including a contact area disposed on the open endof the first guide leg; a plurality of holes disposed on the ring, aplurality of protrusions extending vertically upward from a top surfaceof the ring. The device also includes a third guide member having acylindrical first tube; and a horizontal plate connected to thecylindrical first tube having a top surface and a lower surface, whereinthe lower surface includes the engagement surface for engagement withthe first guide member; and a plurality of holes disposed on the plate,wherein posts protruding from the top surface of the semi-circular ringare capable of entering the plurality of holes disposed on the plate toengage the first guide member with the third guide member. The devicealso includes a fourth guide member having a cylindrical second tubecapable of being connected to the first tube, wherein the outsidediameter of the second tube is less than the inside diameter of thefirst tube to allow engagement; and means for engaging the second tubeto the first tube. The plurality of first guide legs have the same ordifferent lengths depending on the patient's specific needs, and thecontact areas include flat, concave, and convex shapes to fit apatient's hip joint.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred features of the embodiments of the present invention aredisclosed in the accompanying drawings, wherein similar referencecharacters denote similar elements throughout the several views, andwherein:

FIG. 1 is a top/front perspective view of a first guide according to anembodiment of the present invention;

FIG. 2 is a top/front perspective view of a first guide and a secondguide according to an embodiment of the present invention;

FIG. 3 is a bottom view of a first guide and a second guide according toan embodiment of the present invention;

FIG. 4 is a drawing depicting an acetabulum;

FIG. 5 is a top/front perspective view of a first guide and a secondguide engaged with an acetabulum according to an embodiment of thepresent invention;

FIG. 6 is a front perspective view of a first guide engaged with anacetabulum according to an embodiment of the present invention;

FIG. 7 is a front perspective view of a third guide with a reameraccording to an embodiment of the present invention;

FIG. 7A is a front perspective view of a third guide with a reameraccording to an embodiment of the present invention where the reamerincludes a plurality of holes;

FIG. 8 is a front perspective view of a first and third guide with areamer engaged with a hip joint according to an embodiment of thepresent invention;

FIG. 9 is front perspective view of a first guide engaged with anacetabulum and a permanent acetabular cup in the socket of a hip jointaccording to an embodiment of the present invention;

FIG. 10 is a front perspective view of a first guide and a third guidewith a cup impactor to drive the permanent cup into the socket of a hipjoint according to an embodiment of the present invention;

FIG. 11A is a drawing depicting a healthy acetabulum and femur;

FIG. 11B is a drawing depicting an acetabulum and femur withosteoarthritis;

FIG. 12 is a drawing depicting an acetabulum;

FIG. 13 is a drawing depicting an acetabulum and femur;

FIG. 14A is a drawing depicting a hip joint with osteoarthritis;

FIG. 14B is a drawing depicting a hip joint after THA surgery;

FIG. 15 is a top/side perspective view of a first guide engaged with ahip joint according to an embodiment of the present invention;

FIG. 16 is a front perspective view of a first guide engaged with a hipjoint according to an embodiment of the present invention;

FIG. 17 is a side perspective view of a first guide engaged with a hipjoint according to an embodiment of the present invention;

FIG. 18 is a top/side perspective view of a first guide and a secondguide engaged with a hip joint according to an embodiment of the presentinvention;

FIG. 19 is a front perspective view of a first guide and a second guideengaged with a hip joint according to an embodiment of the presentinvention;

FIG. 20 is a top perspective view of a first guide and a second guideengaged with a hip joint according to an embodiment of the presentinvention;

FIG. 21 is a top/side perspective view of a first guide, third guide andfourth guide with a reamer engaged with an acetabulum according to anembodiment of the present invention;

FIG. 22 is a top/side perspective view of a first guide, third guide andfourth guide with a reamer engaged with an acetabulum according to anembodiment of the present invention;

FIG. 23 is a top perspective view of a first guide, third guide andfourth guide with a reamer engaged with an acetabulum according to anembodiment of the present invention;

FIG. 24 is a bottom/front perspective view of a first guide according toan embodiment of the present invention;

FIG. 25 is a front view of a first guide according to an embodiment ofthe present invention;

FIG. 26 is a rear view of a first guide according to an embodiment ofthe present invention;

FIG. 27 is a bottom view of a first guide according to an embodiment ofthe present invention;

FIG. 28 is a top view of a first guide according to an embodiment of thepresent invention;

FIG. 29 is a top/side perspective view of a second guide according to anembodiment of the present invention;

FIG. 30 is a bottom/side perspective view of a second guide according toan embodiment of the present invention;

FIG. 31 is a rear view of a second guide according to an embodiment ofthe present invention;

FIG. 32 is a front/top perspective view of a third guide according to anembodiment of the present invention;

FIG. 33 is a top/rear perspective view of a third guide according to anembodiment of the present invention;

FIG. 34 is a side perspective view of a third guide according to anembodiment of the present invention;

FIG. 35 is a bottom/side perspective view of a reamer according to anembodiment of the present invention;

FIG. 36 is a top/side perspective view of a reamer according to anembodiment of the present invention;

FIG. 37 is a bottom/side perspective view of a fourth guide according toan embodiment of the present invention, showing the side of the fourthguide that connects to the third side;

FIG. 38 is a bottom view of a fourth guide according to an embodiment ofthe present invention, showing the side of the fourth guide thatconnects to the third guide;

FIG. 39 is a top/side perspective view of a fourth guide according to anembodiment of the present invention;

FIG. 40 is a perspective view of a reamer, third guide and fourth guideaccording to an embodiment of the present invention including a dashedline that shows how they are connected together;

FIG. 41 is a perspective view of an assembled reamer, third guide andfourth guide according to an embodiment of the present invention;

FIG. 42 is a top/front perspective view of a first guide according toanother embodiment of the present invention, different from theembodiment shown in FIG. 1;

FIG. 43 is a front/top perspective view of a third guide according toanother embodiment of the present invention, different from theembodiment shown in FIGS. 32-34; and

FIG. 44 is a front/top perspective view of the first guide shown in FIG.42 connected to the third guide shown in FIG. 43.

DETAILED DESCRIPTION

The embodiments of the present invention will now be described morefully hereinafter with reference to the accompanying drawings, in whichpreferred embodiments of the invention are shown. This invention may,however, be embodied in many different forms and should not be construedas limited to the illustrated embodiments set forth herein. Rather,these illustrated embodiments are provided so that this disclosure willbe thorough and complete and will convey the scope of the invention tothose skilled in the art.

In the following description, like reference characters designate likeor corresponding parts throughout the figures. Additionally, in thefollowing description, it is understood that terms such as “top,”“bottom,” “side,” “front,” “back,” “inner,” “outer,” and the like, arewords of convenience and are not to be construed as limiting terms.

Use of a patient-specific surgical guide/template is a relatively newtechnique. It is usually designed in a computer surgical planningprocedure based on a patient's bone geometry (a three-dimensionalreconstruction of CT or MRI images). When the computer surgical plan isapproved by a surgeon, the template can be manufactured using plasticmaterials or the like. The surgical guide/template may be manufactured,for example, through the use of three-dimensional (3D) printingtechnology, stereolithography, or the like. The template can be fixedonto a unique area of the bone and includes a structure that can guide areamer to remove bone with certain orientation and depth. The templatecan also help to place the permanent acetabular component.

FIGS. 4, 11A, 11B, 12, 13, 14A, and 14B show a hip joint 1.Specifically, FIGS. 14A and 14B depict a rendition of a hip joint 1 withosteoarthritis 2 and a rendition of a hip joint 1 with a THA implant 3,respectively. In addition, FIG. 11A depicts a healthy hip joint 1, wherethe acetabulum 4 is the socket shaped concave structure in the pelvicbone 5 that is lined with healthy cartilage 6. The acetabulum 4 includesan acetabular rim 7, an acetabular notch 8, and an acetabular socket 11.The femoral head 9 of the femur 12 (thigh bone) acts as a ball that fitsinto the acetabular socket 11. These components form the main structureof the hip joint 1.

As described above, reaming is a process used by surgeons to removearthritic bone from the acetabulum 4, where a reamer 501 is used toremove diseased bone and cartilage. Reaming also aids in providing thecorrect size of the new socket for an implant (acetabular component) 14.

The embodiments of the present invention were developed through computerplanning and simulation of various surgeries such as THA, total kneearthroplasty, trauma surgeries, and craniofacial surgeries. Theembodiments of the present invention include a patient-specificacetabular reaming and guide device 100, methods of using the same, anda system that includes the device 100 in order to perform a THA surgery.

Specifically, the embodiments of the present invention include anoptimal surgical plan (implant selection and placement) based on apatient's specific anatomy before the actual surgery. Furthermore, theembodiments of the present invention include a patient-specific surgicalguide system that improves the accuracy of acetabular reaming andimplant placement in THA surgery, reducing healthcare costs, andimproving clinical outcomes.

The system of the preferred embodiment of the present invention includescreating a three-dimensional (3D) computer model (or series of computermodels) of the patient's pelvis 5 and femur 12 using CT or MRI scans ofthe patient. The system further includes a computer-based surgerysimulation that is conducted to determine an optimal surgical plan,which will include the size and placement of the acetabular cup 14 andfemoral stem.

FIGS. 1-10 will now be described.

As shown in FIGS. 1 and 2, in a preferred embodiment of the presentinvention, the first guide 101 and the second guide 201 connect with oneanother, where the second guide 201 includes a connecting member 206having a preferred rectangular shape having a male protrusion (notshown) at a free end that fits into an alignment hole 114 in the firstguide 101, which may be in the form of a square hole as shown in FIG. 1.The “means for connecting” as used in the claims includes connectingmember 206 and equivalents as appreciated by a person of ordinary skillin the art. First guide 101 generally has the shape of a semi-circularring with preferably three circular guide posts 112 protrudingvertically upwards from the upper surface of the first guide 101 and aplurality of legs 102 protruding vertically downward from the lowersurface of the first guide 101. The first guide includes openings 108for securing members such as screws to secure the first guide to apatient's hip joint; where angular securement is desired, a side of thering may include a cylindrically shaped member having an opening 109 fora securing means such as a screw to secure the first guide 101 to thepatient's hip.

As depicted in FIGS. 1-3, in a preferred embodiment of the presentinvention, the first guide 101 includes a plurality of first guide legs102 extending vertically downward from the lower surface of the firstguide 101. The second guide 201 includes a plurality of second guidelegs 202 that preferably extend vertically downward from the lowersurface of the second guide 201. The legs 102, 202 include contact areas104 (highlighted in FIG. 3) that can contact and maintain the guides101, 201 at specific areas on the acetabular rim 7. The legs 102, 202and contact areas 104 uniquely locate the guide device 100 relative tothe acetabulum 4. The legs 102, 202 preferably include a rectangularshape but may include certain designs and shapes as required bypatient-specific demands based on the condition of the hip joint andamount of required reaming. The contact areas 104 are preferablydisposed on the lower surfaces of the legs 102, 202 and can includeflat, concave or convex shapes that match a patient's hip joint in orderto effect a secure base and fit on the hip joint; as used in the claims,the “open end” of the legs means the end of the leg not attached to thesurface of the semi-circular ring or second guide rim 204. In addition,the lengths of the legs 102, 202 may be the same or vary based on thenumber of legs needed and patient needs. In addition, the location andamount of the legs 102, 202 on the lower surface of the guides 102, 202may vary based on the patient's needs. The legs 102, 202 shown in thefigures are fixed; however, other embodiments of the present inventionallow for certain movement in the clockwise or counterclockwisedirection to allow a doctor to position the legs on a patient's hip.

One of the goals of the second guide 201 is to provide extra contacts,secure the guide device 100 more accurately, and increase the stabilityof the guide system. In some embodiments of the present invention, thesecond guide 201 may not be needed. The second guide 202 includes apreferred shape and design shown in FIG. 2 having an internal secondguide rim 204 having an arc 232 and horizontal brackets 234, 236 (shownin FIG. 3) that allows it to fit comfortably inside first guide 101 andsecured to same by connection means 206. The termination point 238 ofhorizontal brackets 234, 236 preferably includes a leg 202 a (shown inFIGS. 2 and 3) for further securing the first guide 101 and second guide202 to the patient's hip. The brackets 234, 236 preferably include a 12o'clock to 3 o'clock orientation, respectively, having a substantially90 degree relationship between the legs (the word “substantially” beingused as the angular relationship may vary by 5-10 degrees) with thesecond guide rim 204 preferably connecting the two brackets 234, 236 atthe relative ends 238, 240 of the semi-circular ring of the first guide101 as best shown in FIGS. 2 and 3.

As shown in FIGS. 3-5, in a preferred embodiment of the presentinvention, after the second guide 201 is placed on or inside the firstguide 101, the first guide 101 and second guide 201 are placed on theacetabulum 4 by finding the correct place where the contact areas 104fit properly. Then, in an embodiment of the present invention, screws orother securing means known in the art are inserted through holes 108 or109 as needed to lock the first guide 101 onto the acetabulum 4. Anembodiment of the present invention includes a special contact area 104a that engages with and fits to the acetabular notch 8 therebypreventing rotation of the guide device 100. The engagement of thespecial contact area 104 a and acetabular notch 15 further improves thepositioning and stability of the guide device 100.

As depicted in FIGS. 6 and 7, in a preferred embodiment of the presentinvention, the second guide 201 is then removed to allow a reamer 501 togo into the socket of the hip joint 1. As shown in FIG. 7, the reamershaft 502 will go through a third guide 301 and fourth guide 401. In anembodiment of the present invention, the reamer shaft 502 includes astop 506 from the reamer shaft 502, the stop 506 being in the form of asmall post, square, rectangular, or triangular projection. The stop 506is capable of controlling the depth of the reaming. As best shown inFIG. 33, an embodiment of the present invention includes threeengagement holes 304 in the third guide 301 that allow for theengagement of the three guide posts 112 (see FIG. 1) which project fromthe first guide 101 (see FIG. 8 for engagement of first and thirdguides). A person of ordinary skill in the art will readily understandthat the embodiments of the present invention may include more or lessthan three guide posts 112 and engagement holes 304 based on the desiredapplication of the device. FIG. 7A is a front perspective view of athird guide and fourth guide with a reamer according to an embodiment ofthe present invention where the reamer includes a plurality of openings505 for bone removal during the reaming process.

When using the guide device 100 of a preferred embodiment of the presentinvention, once the acetabular socket is ready (i.e., enough bone hasbeen removed), a permanent acetabular cup 14 (see FIG. 9) may be placedinto the socket. Then, in an embodiment of the present invention, thethird guide 301 can be used with a cup impactor 500 and mallet (notshown) to drive the cup 14 into the socket with a planned orientation(see FIG. 10).

As depicted in FIGS. 15-23, the system of the preferred embodiment ofthe present invention further includes at least a portion of a device100. In a preferred embodiment of the present invention, the device 100includes a first guide 101, a second guide 201, a third guide 301, and afourth guide 401.

As further shown in FIGS. 24-31, in a preferred embodiment of thepresent invention, the first guide 101 has at least three first guidelegs 102 with contact areas 104 that congruently fit with specificlocations disposed both on, and directly outside of, the acetabular rim7. In an embodiment of the present invention, at least one leg 102 isextended into and contacts the acetabular notch 8 to avoid rotationalong the longitudinal axis X of the device 100. An embodiment of thepresent invention allows the first guide 101 to be attached on theacetabular rim 7 at a specific location. A means for fastening the firstguide 101 is then used for securing the first guide 101 to the pelvicbone 5. The means for fastening the first guide 101 may include screwsor the like, for example, including but not limited to bolts, dowels,pins, or the like inserted through holes 108, 109. The screws are ableto penetrate the first guide legs 102 to fix the first guide 101 tightlyonto the acetabulum 4. The first guide 101 of a preferred embodiment ofthe present invention also includes at least three first guide posts 112that can interlock to other fixtures (such as the third guide 301 in apreferred embodiment of the present invention).

In a preferred embodiment of the present invention, the second guide 201includes second guide legs 202 that enable the second guide 201 toengage the pelvic bone 5. The second guide 201 also includes a secondguide rim 204 that aligns with the first guide rim 110 having the shapeof a semi-circular ring to form a tight and stable connection. Thesecond guide 201 may further include a connecting member 206 thatcooperates with an alignment hole 114 on the first guide 101. The secondguide 201 further stabilizes the device 100 such that it is unable tomove (any little movement will greatly affect the accuracy of thereaming and placement of the cup 14 of an implant 3). In a preferredembodiment of the present invention, the third guide 301 (and fourthguide 401) includes a tube 302 (and 402) that guides the reamer shaft502 of a reamer 501 and allows the reamer 501 to remove the socketsurface in a precise predetermined manner. In a preferred embodiment ofthe present invention, the fourth guide 401 also includes a mechanism(length of the tube 402) to control the depth of reaming as well as theposition and orientation of the cup 14 of the implant 3. This reamershaft preferably includes a stop 506 or the like.

The preferred sequence of using the device 100 includes: putting guides101 and 201 together; attaching them onto the right place of theacetabulum 1; applying screws through holes 108, 109 on first guide 101to fix the first guide 101 onto the acetabulum 1; removing guide 201;connecting guide 301 with guide 401, putting the reamer 501 throughguides 301 and 401; and connecting guide 301 with guide 101 to ream theacetabulum 1.

The device 100 preferably includes guides 101, 201, 301, 401, and reamer501. The combination of the guides 101, 201, 301, and 401 ensures thatthe socket surface reaming and cup placement are done according to thecomputer-based optimal surgical plan according to an embodiment of thepresent invention.

The embodiments of the present invention therefore include custom-fitguides 101, 201, 301, 401 that are included in a main device 100 for usein THA surgery. The custom-fit surgical guides 101, 201, 301, 401 aredesigned to improve reaming the acetabular socket 11 and assist inplacing the implant 3. Compared to traditional freehand THA and MISsurgery known in the art, the surgical guide system 1 of the embodimentsof the present invention can achieve easy, accurate, reproducible, andconsistent cup 14 placement. In other words, the clinical outcomes arepredictable and more reliable when using the embodiments of the presentinvention. Compared to image guided navigation surgery known in the art,the device 100 of the embodiments of the present invention hascomparable accuracy and consistency, but lower instrument costs andshorter operative time. Additionally, manufacturing of the device 100 ofthe embodiments of the present invention is relatively easy and costeffective.

A preferred embodiment of the present invention includes at least threefirst guide legs 102 with a small footprint, where the contact areas 104are on or close to the acetabular rim 7. Therefore, this embodiment canavoid the over-removal of soft tissue and the possibility of inaccurateguide positioning. The third guide 301 and fourth guide 401 connect withthe reamer 501 in a preferred embodiment of the present invention andcan be easily installed or uninstalled onto the first guide 101 throughthe first guide posts 112. In an embodiment of the present invention,the guides 101, 201, 301, 401 are small and do not include a fullcircle. The guides 101, 201, 301, 401 also avoid confliction with thefemur 12 and soft tissues around the acetabular rim 4. The embodimentsof the present invention are more practical than designs of the priorart.

As described herein, the embodiments of the present invention include apatient-specific surgical guide system. Further, as described herein,the embodiments of the present invention include a device 100. Moreover,as described herein, the embodiments of the present invention include amethod of reaming and placing an implant 3 during THA surgery.Therefore, the embodiments of the present invention include a device,system, and method of THA surgery.

A system and method of using the device 100 according to the embodimentsof the present invention will now be more fully described.

The device 100 of the embodiments of the present invention is designedto solve the problem of improper position and orientation of aprosthetic cup 14 of a THA implant 3. A problem with THA surgery is thatsurgeons have problems obtaining proper position and orientation of thecup 14 in three dimensions. In other words, the cup 14 may be placed inthe hip 1 in an off position or the orientation is a little toohorizontal, a little too forward, a little too backward, or toovertical. It is difficult with a relatively small incision to knowexactly what the proper position and orientation should be for manysurgeons.

The embodiments of the present invention include a device 100 that iscreated using data obtained from a CT or MRI scan of a patient's pelvis.The data obtained from the CT or MRI scan is then inputted into acomputer program. Based on the bone geometry of the patient, atechnician is able to provide a surgical plan and design a device 100according to an embodiment of the present invention.

In a preferred embodiment of the present invention, the device 100 isdesigned using preferably at least three areas of contact on landmarksof the patient's acetabulum 1. The device 100 may be manufactured usinga 3D printer, which can print the device 100 on demand, for example, ina hospital or doctor's office. One skilled in the art will recognizethat the device 100 may be manufactured using alternative methods knowin the art, such as stereolithography, casting, and the like.

As shown in FIGS. 24-31, in an embodiment of the present invention, thefirst guide 101 includes legs 102 that are located on specific bonylandmarks of the pelvis 5. The first guide 101 of the embodiments of thepresent invention is preferably secured so that it is only able to fitinto one position on the pelvic bone 5. In a preferred embodiment of thepresent invention, the first guide 101 is secured to the pelvis 5 usingscrews or the like, which fit through holes 108, 109 in first guide rim110. The holes can be located through the legs 102 of the first guide101. As shown in the figures, a hole may project from the side of thefirst guide 101, which secures the first guide 101 from the side as wellas the top. The first guide 101 is preferably secured to the pelvis 5 ina manner that causes very little tissue stripping. In other words, thefirst guide 101 is preferably secured to the pelvis 5 using a minimalistincision.

FIGS. 24-27 depict the underside of the first guide 101. As shown inthese figures, the contact areas 104 may be designed to interlock withthe geometry of the bone to which the first guide legs 102 are to besecured. In one embodiment, if there is a long leg 103 on the firstguide 101, a side screw hole can be utilized to secure the leg 103 andprevent movement of the first guide 101 when secured. The contact area105 of the long leg 103 may be on the side of the long leg 103. In apreferred embodiment of the present invention, the shape of the firstguide 101 is substantially a semi-circular shape to fit at leastpartially around the acetabular rim 7. One skilled in the art willunderstand that the first guide 101 may include different shapes,however, depending upon the patient's acetabular geometry and thedesired stability of the guide 100. For example, the first guide 101 canbe substantially a complete circular shape, or the first guide 101 canbe substantially a quarter circular shape. As shown in FIG. 24, in apreferred embodiment of the present invention, the first guide 101includes an alignment hole 114 for receiving connecting member 206 ofthe second guide 201 as shown in FIG. 29.

In a preferred embodiment of the present invention as shown in FIGS.28-31, the second guide 201 engages the first guide 101 by fittingadjacent to the first guide rim 110, and the combination of the firstand second guides 101, 201 can then be properly positioned on theacetabular rim 4. The second guide 201 shown in FIGS. 29-31 includesfour second guide legs 202. One skilled in the art will understand thatmore or less guide legs 202 may be present in an embodiment of thepresent invention. As shown in the figures, the legs 202 can includecontact areas that are designed to interlock with the geometry of thebone to which the second guide legs 202 are to be secured. In anembodiment of the present invention, the second guide 201 also includesa second guide rim 204 and connecting member 206 that fits on top of thefirst guide rim 110. The second guide 201 acts as an element to maintainstability and rigidity of the device 100 in an embodiment of the presentinvention. The second guide legs 202 contact and rest upon theacetabular rim 7. The placement of the first and second guides 101, 201can be a relatively quick process, taking less than five minutes tocomplete.

In a preferred embodiment of the present invention, once the secondguide 201 is removed, a third guide 301 shown in FIGS. 32-34 thenengages with the first guide 101. The third guide 301 includes a plate307 having a top surface and a lower surface 303, where the lowersurface preferably includes the engagement surface for engagement withguide 101 and first guide rim 110 by guide posts 112 going throughengagement holes 304 disposed on plate 307. A person of ordinary skillin the art will readily see that the plate 307 as shown in the figuresis generally flat on both surfaces but may include other surfaces orgrooves therein as necessary to facilitate use of the device 100. Inaddition, as shown best in FIG. 33, the plate 307 includes a pie-likeshape, having a first corner A in, for example purposes only, at a 6o'clock position, and a second corner B at an approximate 10 o'clockposition, thereby having an angular relationship between corners A and Bbetween 120 and 160 degrees, with a preferred range of 135 degrees. Thearc C connects corners A and B together, the arc C having a certain arcof curvature or convex shape as shown in FIG. 33. The plate 307 alsoincludes the engagement holes 304, with each hole being preferably ⅜inch in diameter but like other dimensions specified herein, may varydepending on the specific application and unique design for the patient.The engagement holes 304 are preferably laid out on the plate 307 asshown in FIG. 33, with two holes 304 being generally located adjacent tocorners A and B, and the middle hole being generally located in themiddle of the arc C, generally equidistant from the other two holes 304.

The guide 301 also includes a tube 301 having a cylindrical shape with ahollow shaft 306, the wall thickness of the tube being ¼ inch but again,the thickness may vary as understood by a person of ordinary skill inthe art. The outside diameter of the tube is preferably several inches.As best shown in FIG. 34, the tube includes a top open end 309 andbottom end 310 connected to the plate 307. The preferred length of thetube 302 is 3 inches but this distance may vary as understood by aperson of ordinary skill in the art and required depth of reaming. Asshown in FIG. 34, the tube 302 and plate 307 normally are provided asone unit but in certain embodiments they may be provided separately andattached before use in ways understood by a person of ordinary skill inthe art. The bottom end 310 of the tube 302 is preferably attached onthe top surface of plate 307 but may be connected on an interiorcircumference of the plate 307, where the bottom end 310 is flush withthe bottom surface 303 of the plate 307. As shown in FIGS. 32-34, theinterior shaft at the first end 309 of the tube 302 preferably includesat least two square or rectangular projections 311, each projectionhaving a length of ⅕ inch and a width of ⅙ inch understanding of course,that the projections can take the shape of an oval, circular or otherdesign as understood by a person of ordinary skill in the art. Theprojections 311 are also preferably disposed approximately 180 degreesapart from each other but this can vary as well depending on patient anddevice 100 needs.

In another embodiment of the present invention, the third guide 301engages with first guide 101. The third guide 301 includes an engagementarea 303 with engagement holes 304 that engage with the first guideposts 112 disposed on the first guide rim 110 of the first guide 101.One skilled in the art will understand that more or less guide posts 112and engagement holes 304 may be present in an embodiment of the presentinvention. Moreover, one skilled in the art will understand thatalternative means for engaging the first and third guides 101, 301 maybe present in an embodiment of the present invention, for example,including but not limited to snap-fit connections, pins, bolts, screws,hooks, latches, or the like. In a preferred embodiment of the presentinvention, the third guide 301 includes a cylinder or tube 302 that hasa hollow shaft 306 in which a reamer shaft 502 can be placed to properlyalign and guide a reamer 501. In other words, in a preferred embodimentof the present invention, the tube 302 and shaft 306 act as acylindrical bearing that controls the alignment of the reamer 501.

For reference, a reamer 501 is depicted in FIGS. 35 and 36. The reamer501 includes a reamer shaft 502 and a reamer head 504 with embodiment ofthe reamer 501 having holes as shown in FIG. 7. The reamer shaft 502 mayinclude a stop 506 that prevents the reamer shaft 502 from penetratinginto the guide 100 too far and thereby allows the reamer head 504 toachieve a proper depth in the acetabulum 4. As shown in FIGS. 35 and 36,the reamer head 504 has a bowl-like shape known in the art, havingdifferent dimensions based on the patient-specific reaming requirements.

FIGS. 37-39 show preferred embodiments of the fourth guide 401. Asshown, the fourth guide includes a generally cylindrical tube having abottom end 402 for connection to the third guide 301 and specificallyfor connection to the top end 309. As best shown in FIGS. 37 and 38, thebottom end 402 of the tube 401 includes preferably correspond “L” shapedcutouts in the tube, where each L shape includes a vertical leg 404 a,horizontal leg 404 b, and in the other side, vertical leg 404 a andhorizontal leg 404 c, with horizontal legs 404 b and 404 c extending inopposite directions for protrusions 311 from third guide 301 to engagethe legs 404 a and to lock the fourth guide 401 onto the third guide 301when the protrusions 311 engage horizontal legs 404 b and 404 c in theengagement position.

A person of ordinary skill in the art will readily understand that guide401 can be a standard length metallic tube as part of a regular surgicalinstrument, while guides 101, 201 and 301 are patient specific and arepreferably made by a 3D printer or like.

FIG. 40 is a perspective view of a reamer 501, third guide 301 andfourth guide 401 according to an embodiment of the present inventionincluding a dashed line that shows how these members are preferablyconnected together. FIG. 41 is a perspective view of an assembled reamer501, third guide 301 and fourth guide 401 according to an embodiment ofthe present invention. In these figures, guides 301 and 401 are shown asseparate, independent components with unique designs. However, theembodiments of the present invention also include a design shown in FIG.8 where the third guide 301 and fourth guide 401 as provided as onemember 601.

FIG. 42 is a top/front perspective view of a first guide 701 accordingto another embodiment of the present invention, different from theembodiment shown in FIG. 1. In FIG. 1, three guide posts 112 projectfrom the first guide 101 and engage circular holes 304 shown in FIG. 8for engagement of the first and third guides. In FIG. 42, theprotrusions 700 include inverted “L-shaped” members having a verticalleg 704 and horizontal leg 702. The size and dimension of these members700 vary based on a patient's needs but may include several inches inthe vertical and horizontal direction. In a preferred embodiment, FIG.42 shows the horizontal leg 702 of each of the L-shaped members 700pointing in the same clockwise direction. However, a person of ordinaryskill in the art will appreciate that other embodiments include L-shapedmembers 700 with horizontal legs 702 pointing in different directions.The L-shaped members 700 have inner and outer surfaces that arepreferably concave or include a certain arc that corresponds to theinterior arc/shape of the first guide.

FIG. 43 is a front/top perspective view of a third guide 801 accordingto another embodiment of the present invention, different from theembodiment shown in FIGS. 32-34. The third guide 801 shown in FIG. 43includes many of the same features shown in FIGS. 32-34 and as describedabove. However, the openings 804 are generally rectangular and shaped ina way to match the design of the horizontal section 702 of the L-shapedmember 700 shown in FIG. 42 including having similarconcavities/internal arcs of curvature/shapes to match the horizontalsections 702 of the L-shaped members 700.

FIG. 44 is a front/top perspective view of the first guide 701 shown inFIG. 42 connected to the third guide 801 shown in FIG. 43. As shown inFIG. 44, the horizontal sections 702 of the L-shaped members 700protrude through the openings 804 in the third guide. The horizontalplate of the third guide 801 is then moved counterclockwise to lock orsecure the third guide 801 to the first guide 701.

Based on the previously taken CT scan, a surgeon preferably could ream apelvis 5 in one step. Therefore, the embodiments of the presentinvention can allow a surgeon to avoid reaming by starting small andgetting larger and larger with each iteration of reaming. The preferableone step approach to reaming that is possible through the use of thedevice 100 according to the embodiments of the present invention willsave time and increase accuracy. A person skilled in the art willunderstand that a system using the device 100 according to theembodiments of the present invention may include single step reaming,two step reaming, or more if so desired.

Once the acetabulum 4 is reamed to the desired depth and shape, then thecup 14 of an implant 3 may be inserted into the acetabulum 4. Thistypically occurs when the reaming causes the bone to begin bleedingwhich allows fixation of a porous coated implant cup.

The device 100 according to an embodiment of the present invention isalso capable of controlling the orientation of the cup 14 of the implant3. In other words, the cup 14 of a permanent implant 3 can be orientedand positioned by the device 100. This is desirable because, once theacetabulum 4 is reamed, it may be difficult to properly orient the cup14. In an embodiment of the present invention, the third guide 301 andfourth guide 401 are preferably removed from the first guide 101 inorder to release the reamer 501 and place a cup impactor 500. Then thethird guide 301, fourth guide 401 and cup impactor 500 are assembledwith the first guide 101 again. A mallet (not shown) will drive the cup14 of the implant 3 in the acetabulum 4.

In an alternate embodiment of the present invention, the second guide201 is secured to the first guide 101 by screws or the like. In anotheralternate embodiment of the present invention, the second guide 201simply fits onto the first guide 101 in a manner that creates a securefit without any screws or the like.

The device 100 according to the embodiments of the present invention isa fairly rigid construct once it is put together (the first, second,third and fourth guides 101, 201, 301, 401 are engaged on the pelvis 5).

In an embodiment of the present invention, once the acetabulum 4 isreamed, the device 100 is removed and discarded. In an alternateembodiment of the present invention, once the cup 14 is placed, thedevice 100 is removed and discarded. In other words, a preferredembodiment of the present invention is individually designed for aspecific patient and is therefore designed for a one-time use.

A system according to an embodiment of the present invention includes acomputer program that determines where the cup 14 of an implant 3 ispreferably located based on the CT or MRI scan. Then, based on thisinformation, the depth and shape of the reaming will be determined. Oncethe reaming is determined, the device 100 can be designed in order toachieve the proper reaming depth and the proper alignment of the cup 14of the implant 3.

A further embodiment of the present invention includes a stop 506disposed on the reamer shaft 502 in order to prevent reaming to anundesired depth. Alternatively or additionally, the third guide 301 (orfourth guide 401) may include a stop that allows a reamer 501 to achievea proper depth in an acetabulum of the pelvic bone. A stop on the thirdguide 301 may be an additional element (not shown), or it may be createdby the length of the tube 302 itself.

In a preferred embodiment of the present invention, there are preferablyat least three points of contact between the first guide 101 and thepelvis 5. However, a person of ordinary skill will recognize thatalternative embodiments of the present invention may include more orless points of contact and are not limited to the points of contactshown in the figures. In a preferred embodiment of the presentinvention, there are preferably at least three points of contact betweenthe second guide 201 and the pelvis 5. However, a person of ordinaryskill will recognize that alternative embodiments of the presentinvention may include more or less points of contact and are not limitedto the points of contact shown in the figures.

In a system or method of using the device 100 according to theembodiments of the present invention, multiple reamers may be used inorder to achieve the desired depth and/or shape.

The device 100 according to the embodiments of the present invention maybe constructed out of various materials that can be safely used inpatients including, but not limited to, plastic, metal, or the like. Oneskilled in the art will recognize that the device 100 is not limited tobeing constructed out of the materials referenced herein.

The system and method of the embodiments of the present inventionincludes the steps of taking a scan of a person's hip joint 1, usingcomputer software to determine the proper location and orientation ofthe cup 14 of an implant 3 and the depth and shape of the reamingnecessary, designing a device 100 as described herein, and using thedevice 100 to perform the reaming and/or placement of the cup 14 of theimplant 3. The step of designing a device 100 as described herein mayinclude using computer software to determine the ideal size, shape, andpoints of contact. The device 100 may then be created on demand using a3D printer.

The embodiments of the present invention may significantly improve theprecision of reaming and/or cup 14 positioning.

In an embodiment of the present invention, the second guide is integralwith the first guide.

In a preferred embodiment of the present invention, the first guide 101is aligned onto the pelvis 5 with assistance from the second guide 201.In this preferred embodiment, the second guide 201 is removed before thethird guide 301 is engaged with the first guide 101. In an alternateembodiment of the present invention, the second guide 201 remainsengaged with the first guide 101 when the third guide 301 is engagedwith the first guide 101.

The system for designing the device 100 according to the embodiments ofthe present invention may be used for different surgeries besides THA,such as total knee arthroplasty (TKA), total shoulder arthroplasty(TSA), or similar.

We claim:
 1. A device for use in total hip arthroplasty surgerycomprising: a first guide member comprising: a substantiallysemi-circular ring having a top surface and a bottom surface, aplurality of first guide legs protruding vertically downward from thelower surface of the semi-circular ring, the first guide legs includinga contact area disposed on the open end of the first guide leg; aplurality of holes disposed on the ring, a plurality of protrusionsextending vertically upward from a top surface of the ring, and a secondguide member comprising: an arc having an arc of curvature substantiallysimilar to the semi-circular ring, the arc having a top surface andbottom surface first and second horizontal brackets connecting ends ofthe arc and being connected thereto at a termination point, a pluralityof second guide legs protruding vertically from either the lower surfaceof the arc, first or second horizontal brackets; and means forconnecting the second guide member to the first guide member, a thirdguide member comprising: a cylindrical first tube; and a horizontalplate connected to the tube having a top surface and a lower surface,wherein the lower surface includes the engagement surface for engagementwith the first guide member; and a plurality of holes disposed on theplate, wherein the plurality of protrusions protruding from the topsurface of the semi-circular ring are capable of entering the pluralityof holes disposed on the plate to engage the first guide member with thethird guide member; a fourth guide member comprising: a cylindricalsecond tube capable of being connected to the first tube, wherein theoutside diameter of the second tube is less than the inside diameter ofthe first tube to allow engagement; and means for engaging the secondtube to the first tube.
 2. The device according to claim 1, furthercomprising a reamer having a shaft with a reamer head on one end and astop member disposed on the shaft.
 3. The device according to claim 1,wherein the plurality of first guide legs have the same or differentlengths depending on the patient's specific needs.
 4. The deviceaccording to claim 1, wherein the contact areas include flat, concave,and convex shapes to fit a patient's hip joint.
 5. The device accordingto claim 1, wherein the plurality of holes disposed on the ring includecircular holes having different angles with respect to the top surfaceof the ring, and wherein securing members including screws are insertedthrough the holes to secure the first guide member to a patient's hip.6. The device according to claim 1, wherein the plurality of protrusionsinclude circular cylindrical members.
 7. The device according to claim1, wherein the plurality of protrusions include L-shaped rectangularmembers having a vertical leg and a horizontal leg.
 8. The deviceaccording to claim 7, wherein internal and external surfaces of theL-shaped members have arcs of curvature substantially similar to thearcs of curvature for the first guide members, and wherein each of thehorizontal legs of the L-shaped members are pointing in the sameclockwise direction.
 9. The device according to claim 1, wherein thefirst and second horizontal brackets include a 12 o'clock to 3 o'clockorientation, having a substantial 90 degree angle between the brackets.10. The device according to claim 1, wherein one of the plurality ofsecond guide legs protrudes downward vertically at the terminationpoint.
 11. The device according to claim 1, wherein the means forconnecting includes a rectangularly shaped member attached to the secondguide on one end and having a male protrusion at a free end that fitsinto one of the plurality of holes on the ring.
 12. The device accordingto claim 1, wherein the plate includes a pie-like shape, having a firstcorner A oriented at a 6 o'clock position, and a second corner Boriented at an approximate 10 o'clock position, wherein an angularrelationship between first corner A and second corner B is between 120and 160 degrees, wherein the plurality of holes disposed on the plateinclude holes with a general rectangular shape having concave internaland external surfaces and correspond with the plurality of protrusionsdisposed on the ring.
 13. The device according to claim 1, wherein thecylindrical first tube includes a hollow shaft, wherein the tubeincludes a top open end and bottom end connected to the plate, whereinan interior shaft at the top open end of the tube includes at least twoprojections disposed approximately 180 degrees apart from each other forengagement with a fourth guide member.
 14. A device for use in total hiparthroplasty surgery comprising: a first guide member comprising: asubstantially semi-circular ring having a top surface and a bottomsurface, a plurality of first guide legs protruding vertically downwardfrom the lower surface of the semi-circular ring, the first guide legsincluding a contact area disposed on the open end of the first guideleg; a plurality of holes disposed on the ring, a plurality ofprotrusions extending vertically upward from a top surface of the ring,and a third guide member comprising: a cylindrical first tube; and ahorizontal plate connected to the cylindrical first tube having a topsurface and a lower surface, wherein the lower surface includes theengagement surface for engagement with the first guide member; and aplurality of holes disposed on the plate, wherein the plurality ofprotrusions protruding from the top surface of the semi-circular ringare capable of entering the plurality of holes disposed on the plate toengage the first guide member with the third guide member; a fourthguide member comprising: a cylindrical second tube capable of beingconnected to the first tube, wherein the outside diameter of the secondtube is less than the inside diameter of the first tube to allowengagement; and means for engaging the second tube to the first tube.15. The device according to claim 14, further comprising a reamer havinga shaft with a reamer head on one end and a stop member disposed on theshaft.
 16. The device according to claim 14, wherein the plurality offirst guide legs have the same or different lengths depending on thepatient's specific needs.
 17. The device according to claim 14, whereinthe contact areas include flat, concave, and convex shapes to fit apatient's hip joint.
 18. The device according to claim 14, wherein theplurality of holes disposed on the ring include circular holes havingdifferent angles with respect to the top surface of the ring, andwherein securing members including screws are inserted through the holesto secure the first guide member to a patient's hip.
 19. The deviceaccording to claim 14, wherein the plurality of protrusions includecircular cylindrical members.
 20. A device for use in total hiparthroplasty surgery comprising: a first guide member comprising: asubstantially semi-circular ring having a top surface and a bottomsurface, a plurality of first guide legs protruding vertically downwardfrom the lower surface of the semi-circular ring, the first guide legsincluding a contact area disposed on the open end of the first guideleg; a plurality of holes disposed on the ring, a plurality ofprotrusions extending vertically upward from a top surface of the ring,and a third guide member comprising: a cylindrical first tube; and ahorizontal plate connected to the cylindrical first tube having a topsurface and a lower surface, wherein the lower surface includes theengagement surface for engagement with the first guide member; and aplurality of holes disposed on the plate, wherein the plurality ofprotrusions protruding from the top surface of the semi-circular ringare capable of entering the plurality of holes disposed on the plate toengage the first guide member with the third guide member; a fourthguide member comprising: a cylindrical second tube capable of beingconnected to the first tube, wherein the outside diameter of the secondtube is less than the inside diameter of the first tube to allowengagement; means for engaging the second tube to the first tube,wherein the plurality of first guide legs have the same or differentlengths depending on the patient's specific needs, and wherein thecontact areas include flat, concave, and convex shapes to fit apatient's hip joint.